Hydroxyurea has hematologic and clinical efficacy in sickle cell anemia (SCA), but its effects on transcranial Doppler (TCD) flow velocities remain undefined. Fifty-nine children initiating hydroxyurea therapy for clinical severity had pretreatment baseline TCD measurements; 37 with increased flow velocities (> or = 140 cm/s) were then enrolled in an institutional review board (IRB)-approved pr...

In the present study, we show that hydroxyurea-inactivated ribonucleotide reductase protein M2 has a destabilized iron center, which readily releases iron. In addition, evidence is presented which indicates that single or multistep selection for hydroxyurea resistance, in a variety of mammalian cell lines, leads to alterations in the expression of the gene for the iron storage protein, ferritin...

BACKGROUND The development of therapies for sickle cell disease has received special attention, particularly those that reduce the polymerization of hemoglobin S. Hydroxyurea is a commonly used medication because it has the ability to raise levels of fetal hemoglobin, decrease the frequency of vaso-occlusive episodes and thus improve the clinical course of sickle cell disease patients. OBJECT...

Clinical experience with hydroxyurea for patients with sickle cell disease (SCD) has been accumulating for the past 25 years. The bulk of the current evidence suggests that hydroxyurea is well-tolerated, safe, and efficacious for most patients with SCD. Hydroxyurea has proven clinical efficacy for reducing acute vaso-occlusive events including pain episodes and acute chest syndrome. Salutary ef...

Hydroxyurea is a cell-cycle–specific drug that has been used to treat myeloproliferative diseases and sickle cell anemia. We have recently shown that hydroxyurea, like nitric oxide (NO)–donor compounds, increased cGMP levels in human erythroid cells. We show now that hydroxyurea increases endothelial-cell production of NO; this induction of NO in human umbilical vein endothelial cells (HUVECs) ...

Here we report the widespread natural occurrence of a known antibiotic and antineoplastic compound, hydroxyurea in animals from many taxonomic groups. Hydroxyurea occurs in all the organisms we have examined including invertebrates (molluscs and crustaceans), fishes from several major groups, amphibians and mammals. The species with highest concentrations was an elasmobranch (sharks, skates and...

BACKGROUND AND OBJECTIVES Adhesion molecules on the surface of erythrocytes, leukocytes and platelets are involved in vascular occlusion in sickle cell anemia. Hydroxyurea treatment of sickle cell anemia patients leads to clinical improvement and reduces the incidence of vaso-occlusive episodes. It has been previously demonstrated that hydroxyurea treatment also reduces the expression of adhesi...

It has been reported that a 6-h incubation of early S-phase Chinese hamster cells with hydroxyurea promotes DNA overproduction, i.e., replication of DNA a second time within a single cell cycle, and that this could be the basis for gene amplification in drug-treated mammalian cells. When we incubated methotrexate-resistant Chinese hamster cells that were approximately 2 h into the S phase with ...

While laboratory and clinical benefits of hydroxyurea for patients with sickle cell disease (SCD) are well-established, few data describe the extent and implications of non-adherence. We sought to assess adherence to hydroxyurea among patients with SCD and investigate associations between adherence and clinical and economic outcomes. Insurance claims of North Carolina Medicaid enrollees (6/2000...

conclusions in patients with tm, bone widening, trabeculation, paraspinal masses and facial bone deformity were lower than patients with ti, whichcan be related to effectiveness of therapy with blood transfusion irrespective of its adverse effects in tm patients. results all radiologic findings were significantly higher in patients with ti compared to tm (p< 0.05). in patients with ti, only tra...